Stop-motion for sewing-machines.



No. 643,308. Patented Feb. 13, I900.

' A. STEWARD.

STOP MOTION FOR SEWING MACHINES.

(Application filed May 16, 1899.)

(No Model.) 2 Sheets-Sheet [L x B Wifnesses: Invenfor m: Norms PETERS co. PHwo-Lrmo, \vAsmNm-ou, a c.

No. 643,308. Patented Feb. l3, I900.

A. STEWARD.

STOP MOTION FOR SEWING MACHINES.

(Application filed May 16, 1899.)

2 Shaw -Sheet 2.

(No Model.)

Imkefltor Witness es 4/9 7; 074% TATES ll nure ATENT rrrcn.

AURELIUS STEWARD, OF BRIDGEPORT, CONNECTICUT, ASSIGNOR TO THE \VI-IEELER & WILSON MANUFACTURING COMPANY, OF SAME PLACE.

.STOP' -MOTION FOR SEWING- -MACHINES.

SPECIFICATION forming part of Letters Patent No. 643,308, dated February 13, 1900. Application filed May 16, 1899- -Serial No. 717,013. (No model.)

To all whom it may concern:

Be it known that I, AURELIUS STEWARD, a citizen of the United States, and a resident of Bridgeport, in the county of Fairfield and State of Connecticut, have invented certain new and useful Improvements in Stop-Motions for Sewing-Machines, of which the fol lowing is a specification.

The object of my invention is to provide means for propelling sewing-machines and other machinery, whereby the same may be rapidly stopped and started with accuracy and without injury when necessary to do so at short intervals for the introduction of successive pieces of material, as in sewing on of buttons and similar classes of work.

In the accompanying drawings, which form a part of this specification, my invention is shown in Figures 1 and 2 as applied to a sewing-machine of the well-known Wheeler & Wilson No. 12 pattern, Fig. 1 being a vertical View of the rear end of the machine when looking toward the needle and presser-bars, (not shown,) and Fig. 2 the same from the position of the operator when sitting at the machine, only so much of the machine being shown in either case as represents the manner of applying my invention thereto. In these figures the parts of my invention are shown as assembled for use; but such parts as are not clearly distinguishable therein are shown separately in perspective in Figs. 3 to 13, inclusive.

In Figs. 1 and 2, A shows a portion of the overhanging arm of the sewing-machine, and B a tight pulley and C a loose pulley, constituting part of my invention, which are mounted upon the main driving-shaft of the machine in place of the ordinary hand-wheel in common use. The tight pulley B is formed with a brake-cam upon its inner side, which cam is concentric for about one-half of its circumference, increasingly eccentric thereafter, and terminates abruptly at the completion of the circuit, as shown at D in Fig. 1.

In assembling other parts of my invention the bolts E and E are both passed through holes in the frame E and enter suitable holes therefor in the bracket arm A, by which means the frame is immovably attached to the arm of the sewinganachine. In so doing,

however, the bolt E is first passed through the hole in the brake-lever F, and the enlarged part of its stem or body fitting loosely into the lever serves as a fulcrum or pivot on which the latter may turn when in action, as hereinafter explained. The head of the bolt E is made of sufficient length to serve not only as a head proper, but also as a barrier for the brake-lever F to prevent the same from being thrown beyond its proper limit.-

Near the top end of the brake-lever F, by means of the bolt G, is pivotally attached the V- shaped brake H. The brake H is faced with leather, as seen at h, where it comes in contact with the brake-cam D, and the bolt G, on which it pivots, is made eccentric and supplied with a check-nut, whereby the brake may be se-tnearer the cam to compensate for the wearing of the leather, as occasion requires.

At the top of the brake-lever is securely attached the catchI to engage the latch J. This latch, however, constitutes no part of the invention, it being part of an automatic device for throwing any kind of stop-motion. (as called) in or out of action after a predetermined number of stitches, which invention is A the subject of Letters Patent dated December 4,, 1894, No. 530,264. K, as more clearly shown in Fig. 4, is a belt-shifter whose base is pivotally attached to the frame E by means of the bolt L and whose forks astride the driving-belt of the machine.

At the base of the belt-shifter is a pin to engage the hole in the belt-shifter connection M, which in turn, by means of the bolt N, is pivotally attached to the brake-lever F. The operating-lever O is also pivotally attached to the frame F by means of the bolt P, and the operating-lever and the brake-lever F are also joined by means of the connecting-link R, whose two holes embrace loosely a projecting stud on each of these levers for that purpose. The operating-lever O and the link R form thereby a toggle-joint or knee-lever, by the action of which the brake-lever is thrown forward and back, as occasion re quires. However, I do not wish to be confined to thense of the link connections in this respect, since any well-known form of connection between these levers which will effeet the proper movements thereof will a11- swer my purpose equally as wellsuch, for instance, as a cam-slot connection. The opcrating-lever is also supplied at its outer end with a stud O to engage the looped end of the treadle-rod S by which the lever is operated, the treadle-rod having connection at its lower end with treadles (not shown) as in ordinary use. The coiled spring T, Figs. 1 and 2, is for the purpose of throwing the operating-lever upward, and thereby the brake-lever forward and the brake in contact with the brake-cam D, and is held in position by embracing a stud on the under side of the operating-lever and a like stud in a projection upon the frame E, which is thrown out for that purpose.

When connected as described and shown in Figs. 1 and 2, it will be seen that the brakelever F, brake H, and the belt-shifter K will all be operated by the movement of the operating-lever O. The relative position of the brake H and cam D are such that though the brake-lever be relaxed the cam and brake are never entirely out of con tactthat is,the highest portion of the cam cannot pass the forks or arms of the brake without contact, but by rocking the brake upon its pivot forces each arm alternately out of the way at every revolution, this nearness being desirable in order that only the slightest movement of the brake toward the cam may be necessary to arrest the motion of the latter.

As is well understood, the stopping of a sewing-machine for the removal and introduction of work must occurat a certain timeviz., when the needle is up out of the fabric and the formation of the stitch is completed, and the cam D is so timed upon the tight pulley B and driving-shaft as to produce this result.

The solid lines in Fig. 1 show parts of my invention with the operating lever 0 depressed, the brake-lever and brake thrown back, and all held in that position by the engagement of the catch I with the latch J, and the driving-belt U passing over the tight pulley, as seen in Fig. 2, all as when the sewingmachine is in operation. If an indeterminate number of stitches are to be taken, as in sewing short seams of different lengths, the latch J is thrown out of operative connection with the catch I and the parts are retained in operative position by the feet of the operator; but when released, either by the automatic lifting of the latch J, as hereinbefore described, or by the will of the operator, the expansion of the spring T immediately forces the operating-lever O upward, the brake-lever and brake forward, the latter into the path of the enlarged portion of the cam D, as shown by the dotted lines in Fig. 1, simultaneously turning the belt-shifter to cast the upon the loose pulley O, as seen in Fig. 2, belt and stops the machine. In this position it will be seen that the knee-lever formed by the operating-lever O and the connecting-link R is fully extended, the pivots thereof being in a straight line, which renders it impossible for the brake to rebound, and therefore certain to arrest the cam D and stop the machine in correct position at the first revolution, and yet the arrest is so gradual as the enlargement upon the cam slides between the extended arms of the brake that no shock or injury results.

My special object in supporting the brake I-I upon the pivoted lever F is to reduce to a minimum both the friction and the inertia to be overcome in throwing the brake forward.

I claim In a stop-motion for machinery, the combination of the brake-cam, the supportingbracket E, the brake-lever pivoted thereon, the brake-shoe eceentrically pivoted on said brake-lever whereby said shoe may be adjusted to or from the brake-cam with which it is adapted to engage, the operating-lever O, and operative connections between said operating-lever and said brake-lever, substantially as set forth.

Signed at Bridgeport, in the county of Fairfield and State of Connecticut, this 9th day of May, A. D. 1899.

AURELIUS STEWARD.

Witnesses:

F. HURD, O. H. WORTHEN. 

